


A Slow Burn

by Life_sans_Sin



Series: With and Without [4]
Category: Undertale (Video Game)
Genre: Cunnilingus, F/M, Grillby's sexy sexy voice, Porn with Feelings, Sensitive Grillby
Language: English
Status: Completed
Published: 2018-08-18
Updated: 2018-08-18
Packaged: 2019-06-28 23:31:16
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,514
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/15717321
Author URL: https://archiveofourown.org/users/Life_sans_Sin/pseuds/Life_sans_Sin
Summary: In which the title is an absolute lie and this is not a slow burn, what am I saying?





	A Slow Burn

The moon was high, nestled between a few grey clouds that tried desperately to block out Her glorious light, yet failed. The threat of soon coming rains did little to damper the spirits of a young woman, walking alone down the mountain toward the residential town of Taobh. If anything, it only made her all the more joyous. Her glorious goddess was looking down on her with Her swollen beauty and bountiful light, and she could see nearly every single crater and divot upon Her surface. She exhaled a low sigh of bliss, closing her eyes for just a moment as she walked in Her light and...enjoyed the moment.

 

It wasn’t very often that she left her humble abode up in the mountains, save for going food shopping, gathering herbs, work, or the rare bout of dancing under the moonlight… but tonight was special. It was special, because she had sensed a feeling of deja vu. This wasn’t the first time it had happened, no, but this one felt all the more special because she had a date, of sorts.

 

Granted, the other person probably didn’t know that yet...but it would be a date. The moon told her so.

 

Eventually she reached the center of town, at just around ten past midnight, and found herself looking upon a modest brick building with warm brown shutters, and a very large front door. This was, of course, to accommodate anyone who wished to emter it. She knew that well, just by looking… and also because a rather tall monster ducked underneath the high door frame, looking just a touch inebriated and with an owl monster tucked beneath his arm. She nodded to them both, who gave a little wave before they were on their way. She watched them leave for a moment, saying a prayer of safety for them within her mind, before turning back to the still open door and walking inside.

 

As soon as she crossed over the threshold, there was just this overwhelming warmth. Not as in it was too hot, not at all, more like… it permeated everything. Whereas the moon’s light is cool and smooth, like a pane of glass, this light was warm, and soft, like a heated blanket. She shrugged off her initial discomforts, as she knew she’d never fully get used to it, and took the long moment of silence she found herself in to observe the source of this warmth.

 

He was wearing a white button-up shirt and a black vest with matching bowtie, of what she could see, but she had no doubt that the ensemble was finished off with a pair of black slacks and polished black leather shoes. That’s what he always wore, afterall.  His body was made up entirely of flame, but it was different from regular fire. Something...otherworldly about it, that drew her in and made her want to know more. She knew from a time that had long since passed that he had touched her hand, and it felt solid against her skin. She knew that all it would take was an inkling for it to become ethereal.

 

The white spots of heat that made up his eyes shifted to land on her, and she closed the door behind her as he fixed her with a polite smile. She had to remember that, in this time, they had yet to meet.

 

He raised his hands and moved them in a fluid fashion, smooth like smoke, and as quick as fire.

 

**“Welcome. May I fix you a drink?”**

 

She pondered that for a moment, then smiled and gave a single nod, walking up to the bar and hopping up on one of the stools. He seemed apprehensive, for a moment, but when nothing happened he relaxed again, shoulders and hands lowering. She wondered, for a moment, if perhaps he was awaiting a rude sound...though she had no prior experience in this lifetime to tell her such.

 

“Make me something special to you,” she said as she shifted her skirt a bit, and she watched as he nodded and immediately set to work. A bottle was grabbed and tossed into the air, flipping as he caught it behind his back. With his other, now free, hand, he grabbed a tall glass, sliding it across the counter in front of him. The alcohol was poured in, then set down, grabbing a strange teal-colored concoction in a bottle and spinning it around before pouring it in, as well. He finished the drink off with a silvery powder that, as he pinched it in, began to glow like hot embers, making the drink bubble and froth gently upon impact.

 

She watched with fully opened eyes, mesmerized by the process, and when the drink was finally slid on a coaster in front of her, she looked at it much like a child might look at a candy store. Full of wonder and amazement. The man of flame had a small streak of blue pass just over where his cheekbones might have been, if he had them, though it was gone just as quickly as it had arrived. He tapped two fingers on the bar’s top to get her attention and, when she looked up at him again, blinking owlishly, as if pulled from a trance, his hands began to move again in fluent sign.

 

**“It is called an ‘Inferno’s Tempest’...”** Then, bashfully rubbing at the flames that made up the back of his neck, he sighed a bit, the sound not unlike a low hiss.  **“Actually, I am still working on the name. But I have tested it and it is good, I promise.”**

 

She hummed, high in her throat, and smiled, eyes falling half-lidded again as she slid the drink closer to herself. “Inferno’s Tempest, huh? … It looks good, but the name leaves a heavy feel in my mouth.” He nodded in agreement, and she leaned forward to take a sip. Immediately, sparks began to spread across her tongue, warming her on contact. When she swallowed, it warmed her all the way down, making a comfortable heat simmer in her belly.  She sighed in bliss and closed her eyes, leaning to one side on her bar stool, so much so that he almost reached out to steady her. When she opened her eyes, his hand was reached out to do just that, but she sat upright, and he quickly retracted his hand.

 

**“I take it that it is good?”** he asked, a small crease appearing at the corner of what she assumed to be his mouth… oh, he was smirking the slightest bit. She simply nodded, a blissed-out smile on her face as she basked in the warmth surrounding her. It was different… but not unpleasant. She found herself wanting to roll herself up in that warmth.

 

“Very,” was all she said for a long moment, leaning forward to take another sip from her drink. 

 

The quiet murmur of other patrons began to grow lesser and lesser as, one by one, they began to leave. A dog couple, one of which was very heavy with child from the look of things, waved to the fiery bartender as they left, and another set of dog monsters, one leading another by a leash, walked up to the bar to say goodbye, and Grillby started shifting from foot to foot, keeping himself moving. The black and white dog monster gave a grateful smirk before shifting the blades held at his belt, and patting the hulking white dog in front of him on the shoulder as a signal to go. They left without much incident, save for the blind(ish) dog stubbing his toe on the door frame, and Grillby hissed out another sigh and turned back to her.

 

“So,” she began, finger tracing around the rim of her drink. “My Lady told me that monsters are made of magic… is this true?” Her voice lilted with curiosity, brown eyes sparkling with interest, and Grillby found himself being pulled into those eyes. So warm, yet, with a touch of something cold that left him wanting to find out just what it was.

 

To answer her, he nodded, raising his hands to sign, but was cut off by her lulling voice.

 

“Humans have magic, too, you know…” His hands froze, white spots for eyes widening slightly, and she continued on, staring into the concoction within her glass, swirling and sparking and bubbling as she picked it up. “Magic comes in many forms… Some of it is from within, like with monsters. Some of it is studied and learned. And some of it is gifted…” She glanced up from her drink and gave a small, lazy wink, her mouth tilting up at the corners into a smile. “I’ve always wondered what monster magic is like…”

 

**“Perhaps I could show you sometime.”**

 

Her face slackened with the faintest bit of surprise, and he, too, felt his flames brighten and rise higher out of shock. Had he really just said that? Why did he say that? This human was one he didn’t know at all, and yet, he found himself… drawing in closer. Just as he could feel her drawing in closer, like a moth to a flame… no pun intended.

 

Speaking of puns.

 

He glanced around and saw that, without his notice, all of his patrons had left… well, save for one. Sans was nowhere in sight. He hadn’t been in the bar in quite a while, which Grillby wasn’t sure how to feel about. On the one hand, he’s glad his friend had less nights of drinking alone… but on the other--

 

“I”d like that.” She smiled up at him, half-lidded eyes crinkling around the edges, and he felt his soul throb once within his chest. She took another long, long drink from her glass, and he watched the harmless sparks pass across her tongue when it darted out to lick along her bottom lip.

 

He stared a little too long, and prayed that she wouldn’t notice.

 

She did.

 

“Looks like we’re the only ones left…” she murmured, and he nodded once stiffly. His shoulders squared and he drew in a quiet breath, glancing down at the nearly finished drink, and at the door. “...Do you want me to go?”

 

He shook his head far too quickly, too eager to answer, but he couldn’t help himself. She chuckled, low in her throat, and tilted back her glass to drain the remains of it.

 

“Then… about that magic…” Her eyes blazed, the reflection of his own flames dancing in her eyes, and he swallowed thickly, despite having no need to. She leaned her arms against the bar’s top. “If you show me yours, I’ll show you mine.”

 

Another streak of blue rose above his cheeks, flames rising higher in his embarrassment as his hands gripped at the bar’s top. What, exactly, was he supposed to say to something like that?  Why was a stranger asking to see his magic?

 

And, more importantly, why was he considering it?

 

… You know what?

 

Fuck it.

 

He reached out, unhinging one of his hands from the bar and grasped one of hers, her eyes widening a fraction as she made a small sound of realization. A small ‘huh’. His hand was solid, despite his fiery appearance, and it was warm… not hot like one might expect. She knew that he could control his body heat in that way, somehow. Magic, she mused.

 

He went to pull his hand away, but she laced their fingers together, pulling it closer to examine it. There were no lines on his palm, like she had. The orange and yellow and red of his flames contrasted, casting shadows across her cool brown skin. Her eyes, the color of rich mahogany, danced with his flames, and he found himself leaning in closer to her.

 

Maybe this was her magic, he wondered. The ability to pull someone in like this… it was certainly something otherworldly about her, something he couldn’t properly explain.

 

“Tell me something…”

 

He would certainly try, but without one of his hands, that was going to be difficult.

 

“Just what else can your magic do…?” Her voice was low, barely breaking above a whisper, and he felt a shiver run down his spine. Those eyes were looking directly at him, into him, now… and he felt his fingers twitch around hers before she gave a slow squeeze.

 

“... I can show you.” His voice was crackling around the edges, smoky-sounding from misuse, but it seemed to have the desired effect all the same. Her eyes widened, and for a second (just a second), she almost seemed stunned.

 

Then there were lips, pressing against his own, and he struggled for a moment to keep his composure.

 

Everything was heat,

 

Sensation,

 

Color,

 

Unfocused…

 

Focus.

 

He curled his fingers through her dark brown curls and tilted his chin just so, deepening the kiss. She hummed against his lips and moved her hands to rest on his shoulders, smoothing across the silky fabric of his vest and moving to mess with his bowtie. It was quickly untied and left dangling limply around his neck as she next moved on to the buttons… only for Grillby to suddenly pull away. His flames were high, burning brighter than she’d ever seen, and as he slowly untangled his fingers from her hair, she wondered if, perhaps, she had moved a bit too quickly for him.

 

Imagine her surprise, then, when he walked around the bar to lock the front door and drop the blinds.

 

He turned back to her, and she had her hands up, in the universal sign for ‘pick me up’, and he chuckled, a deep, rumbling sound, before crossing the dining area and lifting her up by her thighs. She squeezed his toros with her legs and wrapped her arms around his neck, seemingly unafraid of being dropped or burned. 

 

Yet another thing about her that drew him in…

 

The kiss resumed, and she moaned into his mouth when he felt as bold as to nibble along her bottom lip. He hefted her up into his arms and made his way through the room, around the bar and toeing open an ajar door that led to a flight of stairs. She giggled the whole while, sounding all at once sleepy and eager, and he very nearly tripped when he felt her skirt ride up and his hands touch the soft skin of her thigh.

 

She pressed open-mouthed kisses, hot and wet, against his neck, and they sizzled slightly against his ‘skin’. Distracting as it was, he did eventually make it up the stairs without incident, kicking open the first door on the right which led to a bedroom. A large, neatly-made bed sat in the center of the sparsely decorated room, though she had little time to take in the view as she found herself set delicately on the edge of the bed. Her skirt, already haphazardly covering her lower half, was pushed up completely to reveal that she’d already soaked through her panties, her arousal evident. Grillby let out a shuddering sigh at the sight, reaching out to trace an index finger along the edges of her panties. Her legs spread wide for him, and he wasted no time in pulling them to the side.

 

She threw her head back a bit when something hot lashed across her soaking core, sizzling quietly as she moaned quietly. Glancing back, she saw only the top of Grillby’s head, and she moved her fingers through the ethereal flames down to what was solid, pressing him closer. He moved with earnest, his summoned, fiery tongue pressing circles around her clit and moving down to press inside her entrance.

 

It didn’t take very long for her to reach her first orgasm of the evening, what with the way his fingers lightly traced intricate patterns along her thigh, or the work of his devilish tongue. As she gripped the sheets and breathed out a moan, he sat up, wiping the fluid from his lips with a sizzling hand. She sat up, as well, and reached for his belt.

 

“Wait…” he said gruffly, clearing his throat. She looked up at him, a question alight in her eyes, but none left her lips. Instead, he took her hands in his. “What do you prefer…?”

 

“Surprise me,” she said simply with a smile, and he breathed out another shaky exhale, nodding. Then, where before there had been nothing, there was something straining against the black fabric of his slacks. He undid the buckle and moved to unbutton his vest and shirt, sliding them off and onto the floor. She grabbed his belt and pulled it out, tossing it aside and unbuttoning his slacks, making sure to brush against the front of them for good measure every now and again.

 

She hadn’t necessarily seen a lot of dick in her life, but she was fairly certain this one was her favorite.

 

Made entirely of fire, but still solid somehow, just like his hands had been. When she encircled it with her hand, he growled low in his throat, and she felt her core clench as she imagined riding him.

 

“Goddess above… you’re gorgeous,” she whispered reverently, and he blushed again, a little streak of blue across his face. He moved closer to her, tugging on her skirt and underwear as she lifted her hips to help remove them. Once they were on the floor, along with her shirt, they were bare to one another. His hands moved to cup her small breasts, thumbing over her nipple, and she sighed in bliss. 

 

“No…  _ you _ are, my dear.” She shimmied up the bed to rest on the pillows, her hair splayed around her in thick curls, and she held her arms open for him. He gladly went into them, his length resting against her thigh, hot and heavy.

 

She pressed a kiss to his lips and adjusted herself until his dick was pressed against her entrance. He drew in a breath and pressed forward. As the first inch or so slid inside, he groaned, letting his head fall to rest against her shoulder. When he was finally hilted within her, his body trembled with sensation, and she was moaning against his neck. He wasn’t any bigger than any she had taken before, but he was  _ hot _ . The licking of flames against her inner walls, despite not burning, was overwhelming a sensation.

 

It took several long moments of them just being in each other’s arms before they could move again, but when they did, it was with a tenderness not seen in most one-night-stands. No, this was something greater than that… even if they didn’t really know it yet.

 

Each thrust bounced her small tits, made her breathing hitch, and she struggled to keep her eyes open as he fucked her. He opened his mouth, and there were fiery fangs there, just begging to be buried into her soft flesh… and she welcomed it. She pulled him closer to her shoulder, until finally, he bit down. She moaned loudly, pulling him closer, deeper, with her legs.

 

The light of the moon shone down upon them from the open window, and he could’ve sworn that her eyes were glowing in a deep, cold amethyst. A tugging on his soul sent it slowly emerging from his chest, and he didn’t stop it, even as her own deep, purple soul slipped out. Tendrils of purple reached out for his soul, he felt her pleasure resonating within himself, atop his own pleasure. His hips shuddered against her, and he picked up his pace, pulling out only a few inches before thrusting hard.

 

The two hearts, one inverted and white, the other not, danced together between their chests, moving above them when Grillby moved closer, until their chests were touching. 

 

A searing kiss that left her lips red and puffy was the final tipping point, and as her orgasm crashed over her, she could feel Grillby chasing his own end. Her hand slipped between them to circle her clit, prolonging her own orgasm as he thrusted wildly, growling deep in his throat. With one final, powerful thrust, he pressed himself against her and froze, his dick twitching within her.

 

He collapsed atop her, breathing heavily, and she just wrapped her arms around him, running her fingernails gently across his back.

 

There were no words wasted that night. Instead, as soon as his dick dematerialized, he curled himself around her from behind, locking his arms around her waist and burying his face into her hair, inhaling the scent of herbs and smoke. She felt comfortable and warm, nestled in his arms and against his chest, and, before she could even thank him, was falling asleep.

 

He realized this, and thought that the right thing to do would be to wake her…

 

...but instead, he found himself dozing off with her.

 

Whatever this was, whatever talk of magics and monsters and humans, whatever  _ they _ were, it could wait until breakfast.


End file.
